Talk less. Smile more. Don't let them know what you're against or what you're for.
~ Burr's catchphrase.
...How does Hamilton, an arrogant, immigrant, orphan, bastard, whoreson, somehow endorse Thomas Jefferson, his enemy, a man he's despised since the beginning, just to keep me from winning? I wanna be in the room where it happens, the room where it happens, the room where it happens...You've kept me from the room where it happens for the last time...
~ Burr's villainous breakdown.
Aaron Burr (based on the historical figure of the same name) is the main antagonist of the 2015 Broadway rap musical Hamilton and the 2020 Disney film of the same name, also serving as the narrator. He is a passive politician who starts off as Hamilton's friend but later becomes his rival as his envy of the latter's political success drives him to blackmail and finally murder.
He was portrayed by several actors across different runnings of the show but was portrayed first and most famously by Leslie Odom Jr.
Burr is initially a very humble and reclusive man, focused entirely on carrying on his family's legacy, but also not wanting to take any rash action. Therefore, he dares not express any clear goals or opinions and doesn't want to start any fights.
When he meets Hamilton, he shares his ideology with him, but when the latter starts becoming successful in being very bold, active, and controversial, Burr grows jealous and decides he wants the same power, even without having any established views.
Thus, he is willing to switch political parties and betray Hamilton, and even goes as far as to blackmail him and challenge him to a duel in which he shoots him. He snaps out of his rage when the gun is fired and laments he will forever be remembered as the man who shot Hamilton, and not for his political achievements.
Hamilton first meets Burr when he travels to New York City as a 19-year-old. He asks his future rival for advice, as Burr graduated college in two years, showing a vast intelligence. Burr reveals it was his parents' dying wish, and the two realize they are both orphans. When Hamilton runs off at the mouth, Burr shuts him down by saying he should talk less, and smile more (as to not get shot) something Hamilton deeply disagrees with.
During the American Revolution's war against the British to become independent, Burr attempts to aid the then-general George Washington with some suggestions, but he is told to leave when Hamilton enters, as Washington favors him. Hamilton becomes the general's right-hand man, to Burr's dismay.
During a ball, Burr attempts to charm the wealthy and beautiful Schuyler sisters but is unsuccessful in his endeavor. Hamilton then marries Elizabeth Schuyler, while having a close semi-romantic connection with her sister Angelica on the side. After the wedding, Burr congratulates Hamilton, but their mutual friend John Laurens reveals Burr has a woman in his life. In private, Burr tells Hamilton it's a lady called Theodosia, and she's married to a British soldier totally ignorant of the situation.
Left to his own devices, Burr begins reflecting on his place in life and relationship with Theodosia, and concludes he will wait for the future to come to pass. He does, however, express some envy of Hamilton's rapid ascension in politics. Burr has a daughter and names her after her mother.
Burr reappears after Hamilton has reached the Compromise of 1790 with the politically opposing Thomas Jefferson. The compromise involves moving the capital closer to Jefferson, and Burr angrily confronts Hamilton. Calmly, Hamilton explains that he profited from the ordeal, and reprimands Burr for not being aggressive himself, stating that he gets nothing by "waiting for it". He asks what Burr even hopes to achieve, and leaves.
Burr realizes his one goal. He wants to be in "the room where it happens". Instead of fighting for his own values, he has a goal fueled by envy, to achieve political power. Right after coming to terms with this, he switches parties and becomes a Democratic-Republican, taking Phillip Schuyler (Hamilton's father-in-law)'s seat in the senate.
Hamilton snaps at Burr for his betrayal, but Burr smugly explains he simply seized the opportunity he saw and tells Hamilton to keep his arrogance in check. Along with his now-allies, Thomas Jefferson and James Madison, Burr notices that Hamilton has a great advantage in his relationship with Washington. They all then decide to confront Hamilton with recorded evidence of papers that suggest fraud.
Hamilton responds (in order to save his reputation) that this was his own money, and that he was paying the husband of a Mrs. Reynolds, a woman who had seduced him so that Eliza wouldn't be apprised of this secret affair. Jefferson and Madison assure Hamilton the people won't know of this, but Burr sinisterly states that rumors only grow, subtly pushing Hamilton to write a pamphlet on the controversy before someone else exposes him.
This backfires horribly, and with Hamilton's political career destroyed, Burr runs for president in 1800. He publicly campaigns (a concept entirely new at the time), and on his door-to-door spree, he meets Hamilton and briefly antagonizes him. This proves to be an ill-advised move, as Hamilton endorses Jefferson, who is also running for president, instead of Burr, despite their many disagreements. Hamilton states that while Jefferson's points have always contradicted his own, the man at least has them, while Burr has no beliefs.
This causes Jefferson to win the election by a landslide, and to rub salt in the wound, Jefferson reveals he plans to get rid of the law that dictates the runner-up gets to be vice-president, ruling Burr out of the equation. This is the point where Burr snaps, and he blames Hamilton for all that has gone wrong.
They organize a duel, and while Hamilton attempts to surrender by aiming his pistol at the sky, Burr still fires, realizing only all too late that his rival had no plans of shooting him. Burr now sees his predicament. In a desperate effort to protect his legacy, he ruined it, as history will always remember him as the villain who shot Hamilton.
They don't need to know me; they don't like you.
~ Burr revealing his true colors to Hamilton.
But Alexander! Rumors only grow. And we both know what we know...
~ Burr implying Hamilton's secret affair with Maria Reynolds will be revealed to the public.
Careful how you proceed, good man, intemperate indeed, good man, answer for the accusations I lay at your feet or prepare to bleed, good man.
~ Burr threatening Hamilton.
Aaron Burr, Sir
The Room Where It Happens
Your Obedient Servant
While the real life Burr indeed did write that he should have known the world was wide enough for both Hamilton and him, he was not immediately remorseful after the duel.
Although in the show it portrayed Burr as Jefferson's primary opposition in 1800, this wasn't the case as John Adams still had quite a bit of support in the North, and Burr and Jefferson worked together to take down Adams rather than compete with each other. The only instance where they competed in the election, was in the contingent election after the tie was declared.
Burr was also seemingly rejected by Jefferson as Vice President, but this wasn't the case, and Jefferson did allow Burr to become the Vice President and changed the original system 3 years later, rather than immediately. Burr also challenged Hamilton to a duel four years after the Election, rather than right after. The cause for the duel was also Hamilton insulting him in press and undermining his political goals, rather than choosing Jefferson.